Albeet p



(No Model.)

A. P. MASSEY.

UAR BRAKE.

No. 368,347. Patented Aug. 16, 1887.

:Iii'jifl WITNESSES INVENTDR W W Mu Q w I UNITED STATES PATENT OFFICE.

ALBERT P. MASSEY, or WATERTOWN, NEW YORK, Assienon TO THE EAMEs vAoUUMBRAKE COMPANY, or sAME rLAoE- CAR BRAKE.

SPECIFICATION forming part of Letters Patent No. 368,347, dated August16, 1887.

Application filed February 11, 1887. Serial No. 227,255. (No model.)

To all whom it may concern:

Be it known that I, ALBERT P. MASSEY, a

citizen of the United States, residing in the city of \Vatertown, in thecounty of Jefferson and State of New York, have invented a new anduseful Improvement in Oar-Brakes, of which the following, taken inconnection with the accompanying drawings, is a specification.

My invention relates especially to improvements in car-brakes, but isnot confined solely thereto.

It consists of a lever suspended by two movable fulcrums, and is for thepurpose of taking up the slack or moving the brakeblocks against thewheels of a car with a moderate force and short stroke of the actuatingmechanism and then applying a much greater pressure against the wheels.

Figure 1 shows the arrangement of lever and fulcrums attached to thetimbers of a car, the dotted lines showing its position when revolved.Fig. 2 is a side view of same.

A B is a bent lever suspended at two points, G and I, to the movablefulcrums I and G by the links 0 and D. These links are attached by pins,about which they are free to revolve, to the rigid support E.

M and Q are timbers of a car.

P is a diaphragm used in the vacuum system of car-brakes.

N is a rod connecting diaphragm P with the lever A B at H.

L is a rod connecting the ordinary brakelevers with the lever A B at K.

H H represent the path of the point H as the lever moves, and is markedoff in equal spaces by the Roman numerals.

K K represent the path of the point K and is marked with Arabic numeralsto show the points which correspond with those marked with Romannumerals in the path of the point H.

In the beginning of the stroke the virtual fulcrum of lever A B is at I,while link D is simply a guide. In the latter part of the stroke the pinG or G is the fulcrum and the link 0 is a guide. In intermediatepositions the virtual fulcrum is a point somewhere be tween the pins Iand G.

-In operating a Vacuum brake, air is exhausted from the diaphragm N,which causes the flexible diaphragm to' collapse and draw on the rodLwith a pull proportional to the area of the diaphragm and thedifference between the vacuum inside and the atmospheric pressure. Inordinary cases the brake-rod K is attached directly to the diaphragm,and about one-half of the stroke of the diaphragm 'is consumed inbringing the brake-blocks against the wheelsa process that requires amuch smaller expenditure of force. In my device, when the pull or motionof diaphragm Nbegins, the lever A B begins to revolve about the fulcrumI, with a short leverage, I H, for the diaphragm and a long leverage, IK, for the brake-rod, so that the movement of the brake-rod would bemuch greater than that of the diaphragm. As the point H is drawn towardH the virtual fulcrum travels along between I and G, thus increasing theactual leverage of the diaphragm and decreasing the leverage of thebrake-rod, so that when the brake-rod has been moved half its distance,or sufficient to bring the brake-shoes against the wheels, the diaphragmis pulling on the longest arm of the lever, and consequently with muchgreater force on the brake-shoes than when taking up the slack. It isobvious that this arrangement of lever and links would operate the samewhether the motive force be a diaphragm, as shown, a piston andcylinder, a brake-staff and hand-wheel, or any other mode of applyingpower.

What I claim, therefore, and desire to secure by Letters Patent, is-

The lever A B, in combination with the fulorums I and G, and the links 0and D revolving about fixed points F and J, for the purpose set forth.

In testimony whereof I have signed my name to this specification,in thepresence of two subscribing witnesses, on this 9th day of February, A.D. 1887.

ALBERT r. MAssEY.

Witnesses WALTER WARD, MIOHAEL "J. MoRKIN.

